The Sigma-Aldrich Pure-Pac II returnable containers require the Micromatic MacroValve coupler for dispensing chemical. The Dispense Head Coupler Kit includes the MacroValve coupler along with the standard components needed to connect to either 1/2in. or 3/8in. diameter transfer lines. All of the hardware in the kit is supplied in a foam-lined plastic case. See Technical Bulletin AL-236 for assembly instructions.